Cupola furnace provided with an ash collector



June 14y 1955 E. T. DouGLAss, JR

CUFOL FURNACE PROVIDED WITH AN ASH COLLECTOR 2 Sheets-Sheet l Filed July 27, 1954 INVENTOR \& m

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June 14, 195 E. T. DouGLAss, .JR 2,710,748

CUPOLA FURNACE PROVIDED WITH AN ASH COLLECTOR Filed July 27, 1954 2 Sheets-Sheet 2 INVENTOR 50W/9kb 72 DOUGLHSSI/R.

ATTORNEYS United States Patent O CUPOLA FURNACE PROVIDED WITH AN ASH COLLECTOR Edward T. Douglass, Jr., Birmingham, Ala.

Application July 27, 1954, Serial No. 445,946

8 Claims. (Cl. 266-31) This invention relates to means for arresting and collecting the solids heretofore discharged from a cupola furnace, and has for its object the provision of an improved design cupola and apparatus employed in connection therewith which shall be effective to entrain the solids in an upward spirally moving air stream in the cupola and entrap them before they are discharged.

A further object of my invention is to induce an upwardly spiral movement of air and solids laden furnace gases in the upper part of the cupola whereby to cause the solids in the mixture to be forced around the wall of the cupola by centrifugal force and be there entrapped before they can be discharged.

More specifically my invention comprises an extension on the upper end of a cupola which may comprise thirty per cent or more of the total height of the cupola, rf.

and induce into the lower part of this extension tangential currents of air which travel upwardly in unobstructed spiral paths in the cupola, cooling the gases and the extension and entraining with them the solids which are conveyed to a suitable separator where they are collected.

As is well known in the art to which my invention relates, cupola furnaces create a great deal of solids in the form of ash, cinders and the like which are carried out of the stack by the blast. For this reason, foundries have heretofore been located in less populous sections of a city. With the increase in density of population it has now become of prime importance to the health and cleanliness of a community as well as of the workmen around foundries to provide means for entrapping and collecting such solids.

Apparatus embodying features of my invention is illus trated in the accompanying drawings, forming a part of this application in which:

Fig. 1 is an elevational view with parts broken away .if

and in section, of a cupola furnace constructed in accordance with my invention;

Fig. 2 is a plan view looking in the direction of the arrows II-II in Fig. 1;

Fig. 3 is a sectional view taken along the line III-III of Fig. l;

Fig. 4 is a sectional View taken along the line IV--IV of Fig. l; and,

Fig. 5 is a detail sectional view taken along the line V-V of Fig. 1.

Referring now to the drawings for a better understanding of my invention, I show in Fig. 1 a base, or foundation 10 upon which rests a conventional cupola embodying a stack 11, a windbox 12, a charging door 13, and a blower for the blast 14. My improved means for collecting solids driven upwardly in the stack 11 by the blast comprises an extension 16, which, at the bottom, is of the same diameter as the stack 11 of the cupola and is secured thereto by any suitable means at 17. The extension tapers gradually inward toward the top as shown at 18 in order to increase the velocity of the ascending gases passing upwardly in the stack.

2,710,748 Patented June 14, 1955 Around the lower portion of the extension are provided a plurality of openings 19, see Fig. 4. Extending outwardly over each of the openings 19 is a cup shaped vane 21 to direct air tangentially into the extension. The extreme upper end of the extension 16 is curved, or

turned over slightly outwardly as shown at 22, to pro` vide easier passage for solids out of the stack.

Surrounding the upper end of the extension, and spaced therefrom, is a circumferential wall 23 which, as shown in Fig. 1, extends above the upper end of the tapered end of the extension. Connected to the wall 23 and-extending inwardly and downwardly therefrom is an annu- 1r baie 24, which overhangs the extreme upper end 22 f the extension. Connected to the circumferential wall 3 around its lower edge are a plurality of laterally adjoining hopper members 26, which form the bottom of the solids entrapment chamber formed in part by the circumferential wall 23. The hopper members taper downwardly and have conduits 27 connected thereto at the bottom. The conduits 27 are connected at their lower ends to a common conduit 28 surrounding the cupola and which is connected in turn to a cyclone separator indicated diagrammatically at 29. A suction fan 31 is connected to the upper end of the separator 29 to withdraw gases therefrom and also to aid in withdrawing solids from the extension and delivering them to the separator. Solids delivered into the separator 29 fall into a suitable receptacle 32. The suction fan 31 discharges the gases withdrawn from the conduits 28 and 27 through a conduit 30 which is connected tangentially to the cupola at 35 just below the extension 16. This creates a spiral ow of gases around the cupola which aids to induce a iiow of air into the openings 19.

From the foregoing description, the operation of my improved apparatus will be readily understood. The forced draft, or blast provided by the blower 14, as is well understood, causes a relatively high velocity upward flow of heated gases at relatively low pressure through the cupola stack 11which entrains solids from the charge and carries them upwardly with the blast. These gases passing the lower end of the extension 16 induce ow of air is caused to enter tangentially of the exten-l sion by reason of the vanes 21. This induced air together with the gases introduced at 35, cools the gases and solids and creates a circular motion of the gases and solids being conveyed upward. It also reduces the upward component of velocity of the gases by reason of diverting them into a spiral iiow and increasing their density. The circular motion of the stack gases causes the solids to travel along the sides of the extension 16 due to centrifugal force. The gradual inward tapering of the extension 16 reduces the cross sectional area of the upper end of the extension and increases the spiral velocity of the gases with their entrained solids. As the solids reach the upper end of the extension, they are intercepted by means of the annular bafe 24 and are guided into the solids entrapment chamber defined in part by the circumferential wall 23. The solids then fall downwardly into the hopper members 26 and thence downwardly through the conduits 27 into the conduit 28 from whence they are withdrawn by means of the blower 31 and are collected by the cyclone separator 29.

From the foregoing it will be apparent that I have devised an improved means for entrapping and collecting solids passing upwardly with the vgases in a cupola furnace which is simple and economical of design and reliable in operation.

While i have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited but is susceptible of various changes and modifications without departing from the spirit thereof,

and I desire, therefore, that only such limitations shall be placed thereupon as are specifically set forth in the appended claims.

What I claim is:

l. The combination with a cupola furnace having the usual stack and air blast, of an extension mounted on the upper end of the stack and having a plurality of openings, arranged circumferentially around the lower end thereof, means to admit and direct air tangentially of the stack through said openings, a solids entrapping chamber surrounding the upper end of the stack extension, an annular bat-lle joined to the upper end of the chamber and overhanging the upper end of the extension in position to direct solids into the chamber, and conduits connected to the lower end of the chamber to convey solids away.

2. The combination with a cupola furnace having the usual stack and air blast, of an extension mounted on the upper end of the stack and having a plurality of openings arranged circumferentially around the lower end thereof, means to admit and direct air tangentially of the stack through said openings, a solids entrapping chamber surrounding the upper'end of the stack extension, hopper members joined to thc bottom of the entrapping chamber to receive solids, and conduits joined to the lower ends of the hopper members to convey solids away.

3. The combination with a cupola furnace having the usual stack and air blast, of an extension mounted on the upper end of the stack and having a plurality of openings arranged circumferentially around the lower end thereof, means to admit and direct air tangentially of the stack through said openings, a solids entrapping chamber surrounding the upper end of the stack extension, hopper members joined to the bottom of the entrap- It.;

ping chamber to receive solids, conduits joined to the lower ends of the hopper members to carry solids away, and suction means connected to the lower ends of the conduits.

4. The combination with a cupola furnace having the usual stack and air blast, of an extension mounted on the upper end of the stack and having a plurality of openings arranged circumferentially around the lower end thereof, means to admit and direct air tangentially of the stack through said openings, a solids entrapping chamber surrounding the upper end of the Stack extensionkliopper members joined to the bottom of the entrapping chamber to receive solids, conduits joined to the lower ends of the hopper members to carry solids away, a manifold connected to the lower ends of the conduits, air and solids separating means connected to the manifold, and suction means associated with the separating means effective to cause suction downwardly in the conduits.

5. The combination with a cupola furnace having a stack and air blast means associated therewith, of an extension mounted on the upper end of the stack and tapering inwardly toward the top, a plurality of openings extending circumferentially around the lower part of the extension, vanes mounted on the extension and extending over each opening to direct air tangentially inward of the extension, a circumferential wall spaced from and surrounding the upper end of the extension to form a chamber therebetween, said wall extending above the upper end of the extension, an annular baille member joined to the upper end of said wall and inclined downwardly therefrom to deflect solids into the chamber, hopper members connected to the chamber, and means to deliver solids from the hopper members.

6. The combination with a cupola furnace having a stack and air blast means associated therewith, of an extension mounted on the upper end of the stack and tapering inwardly toward the top, a plurality of openings extending circumferentially around the lower part of the extension, a vane mounted on the extension and extending over each opening to direct air tangentially inward of the extension, a circumferential wall spaced from and surrounding the upper end of the extension to form a chamber therebetween, said wall extending above the upper end of the extension, an annular baille member joined to the upper end of said wall and inclined downwardly therefrom to deflect solids into the chamber, a plurality of hopper members adjoining each other laterally around the bottom of the chamber, conduits connected to the hopper members and means to withdraw solids from the conduits.

7. The combination with a cupola furnace having a stack and air blast means associated therewith, of an extension mounted on the upper end of the stack and tapering inwardly toward the top, a plurality of openings extending circumferentially around the lower part of the extension, a vane mounted on the extension and extending over each opening to direct air tangentially inward of the extension, a circumferential wall spaced from and surrounding the upper end of the extension to form a chamber therebetween, said wall extending above the upper end of the extension, an annular battle member joined to the upper end of said wall and inclined downwardly therefrom to deflect solids into the chamber, a plurality of hopper members adjoining each other laterally around the bottom of the chamber, conduits connected to the hopper members, and a cyclone separator connected to the conduits to withdraw solids therefrom.

8. The combination with a cupola furnace having a stack and air blast means associated therewith, of an extension mounted on the upper end of the stack and tapering inwardly toward the top, a plurality of openings extending circumferentially around the lower part of the extension, a vane mounted on the extension and extending over each opening to direct air tangentially inward of the extension, a circumferential wall spaced from and surrounding the upper end of the extension to form a chamber therebetween, said wall extending above the upper end of the extension, an annular baffle member joined to the upper end of said wall and inclined downwardly therefrom to deflect solids into the chamber, a plurality of hopper members adjoining each other laterally around the bottom of the chamber, conduits connected to the hopper members, a cyclone separator connected to the conduits to withdraw solids therefrom, a

suction fan connected to the cyclone separator to with- References Cited in the file of this patent UNITED STATES PATENTS Huber Apr. 18, 1893 Hawley Feb. 18, 1930 

